Stapler



FIG. 1 is right side perspective view of a stapler in accordance with an alternate embodiment of the design;

FIG. 2 is a left side view thereof;

FIG. 3 is a front end view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view thereof. 

The ornamental design for a stapler, as shown and described. 